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1.
For the purposes of this paper, biosecure shrimp feeds and on‐farm feeding strategies refer to the “feed, whether live, fresh, or formulated, and the management of the feed on the farm, should not be an entry point of potential pathogens to the shrimp and/or to the culture system.” The paper reviews the different feeds commonly used for the production of farmed shrimp and discusses their potential risks from a disease perspective, including the use of live hatchery and nursery feeds, the use of live and/or fresh food organisms for the production of broodstock, and the use of dry formulated shrimp feeds for shrimp growout operations. In addition, the paper discusses the critical role played by feed‐processing techniques for the pasteurization and destruction of pathogens within shrimp feeds and the need for nutritionists to formulate feeds for optimal nutrition and health, and not just for optimal growth. The importance of the development and implementation of good on‐farm feed management practices by farmers is discussed, including the prohibition of the top‐dressing of pelleted feeds on farm by farmers with unapproved feed additives such as antibiotics. Finally, the paper discusses the responsibilities of farmers, feed manufacturers, and traders regarding the development and use of recommended biosecure shrimp feeds and feeding practices.  相似文献   

2.
We conducted a 16‐wk feeding trial with large juvenile red drum, Sciaenops ocellatus. Four diets were randomly assigned to six replicate tanks per treatment. Three isonitrogenous (ca. 44.5% protein) and isolipidic (ca. 14.1% lipid) extruded diets were formulated to compare a fishmeal‐based diet with diets using alternative protein sources. Diet 1 contained 19.60% fishmeal and 21.42% poultry meals as primary protein sources. Two alternative diets were formulated reducing the fishmeal to 0.61% by substituting poultry meals (33.85%) and soybean protein concentrate (11.55% in Diet 2 and 11.70% in Diet 3). Diet 3 also included Allzyme Vegpro® and Allzyme® SSF at 0.04%. Diet 4, a natural diet consisting of chopped cigar minnows, squid, and shrimp, was used as a positive control to compare growth rates of formulated feeds to near maximum growth under these culture conditions. We found that reducing the amount of fishmeal to <1% by using alternative protein sources did not affect the growth rate, survival, or health of red drum but improved assimilation of phosphorus, reduced potential release of P to the environment, and significantly lowered the amount of feeder fish needed in feed. The control diet identified performance benchmarks for future feeds development work.  相似文献   

3.
液态氧在对虾工厂化养殖中的增氧效果   总被引:1,自引:0,他引:1  
试验结果表明,液态氧能使养殖水体持续维持较高的溶解氧(DO)含量(充气压力0.15 MPa,DO≥7.0 mg/L),且分布均匀,无DO分层现象.成本分析表明,液态氧增氧的成本略低于动力增氧.  相似文献   

4.
A magnesium budget was prepared for a commercial low‐salinity shrimp farm in the Blackland Prairie region of Alabama for one production cycle. Ponds had previously been used for production and fertilized with magnesium; two ponds (S‐5 and S‐6) for four previous years and one pond (N‐9) for one previous season. Fertilization with sulfate of potash magnesia (K2SO4·2MgSO4 or K‐Mag®) was applied to these ponds to obtain the concentrations of 20 mg/L, averaging 1274 kg Mg2+/ha. Additional inputs of magnesium included groundwater, rainfall, and runoff averaged 441.5 kg/ha. A water budget for ponds indicated that 292.6 kg/ha of magnesium in outflows. The difference in inputs and magnesium outputs resulted mainly from adsorption of magnesium by pond bottom soils. However, the increase in exchangeable magnesium in the upper 15‐cm layer of pond bottom soils was not great enough to account for the difference in total magnesium inputs and magnesium outputs in water and shrimp. Possible explanations for this discrepancy are magnesium precipitation, nonexchangeable fixation of magnesium by clay minerals, incomplete extraction of magnesium, and analytical error. The decreased uptake of magnesium by older ponds, S‐5 and S‐6, indicate that the soils had a diminishing affinity for the cation or an equilibrium concentration is being established.  相似文献   

5.
The use of dietary supplements in commercial shrimp production feeds is increasing because of the need to reduce marine meal (e.g., fish meal) content. Our study evaluated leaching and apparent digestibility of artificial methionine supplements and their use in determining appropriate feeding levels of methionine in practical fish meal replacement diets fed to Litopenaeus vannamei. Three forms of methionine were evaluated: dl ‐methionine HCl, various mineral chelates of methionine, and a short‐chain synthetic methionine polymer. Results showed a significant increase (P < 0.05) in leaching loss of methionine from feeds with decreasing salinity and that leaching was significantly higher for dl ‐methionine than other forms in all salinity treatments. No significant difference was shown in apparent digestibility of methionine among digestibility diets, with the exception of diets supplemented with dl ‐methionine HCl. In two 6‐wk clear‐water growth trials, no significant difference in weight gain was shown by shrimp fed diets containing more than 0.4% methionine (1.14%, as percent of protein). This suggests that an appropriate feed level of methionine for practical plant protein‐based feeds is less than 0.4% of the diet. Results also indicated that mineral‐chelated and polymerized forms of methionine are appropriate for supplementation of plant protein‐based feeds.  相似文献   

6.
宫春光  李凤臣  苏利 《水产科学》2006,25(6):310-311
研究了日本对虾在不同运输方式、装运密度、运输时间下的运输成活率。结果表明:无水运输日本对虾密度在33.3 kg/m2时,3 h以内的运输成活率均在95%以上;无水充氧运输日本对虾密度在33.3 kg/m2时,13 h以内的运输成活率均在90%以上。  相似文献   

7.
Supplementation of microalgae and Artemia nauplii with practical formulated feeds containing fresh or dried Artemia biomass for larval rearing of black tiger shrimp, Penaeus monodon, was assessed. Five feeding treatments were carried out in a recirculating seawater system with fifteen 30-L fiberglass tanks. Shrimp nauplii were stocked at a density of 150 L?1 for 23 days. In the control treatment, live feed was supplemented with commercial formulated feed (Inve Aquaculture NV, Belgium). In two other treatments, live feed was supplemented with a pelleted feed based on either fresh or dried Artemia. In the remaining two treatments live feed was supplemented with a combination of 50% commercial feed and 50% fresh or dried Artemia feeds. Overall, performance of PL in the combination treatments (commercial feed and Artemia diets) were equal to or better than those fed commercial feed alone as seen by the better growth rate and higher resistance to formalin stress. The results indicate that feed containing fresh or dried Artemia biomass can partially supplement live feeds for larval rearing of P. monodon.  相似文献   

8.
ABSTRACT

A liquid fermentation process to bioconvert shrimp by-products was developed with two species of fungi, Boletus edulis and Suillus bovinus. Angiotensin I-converting enzyme (ACE) inhibitory, antioxidant activities of bioconverted products and the deodorization effect of fungal bioconversion were determined. Two species of fungi could grow quickly in shrimp by-products medium and deodorize shrimp by-products. Bioconverted products had higher ACE inhibitory and antioxidant activities than control medium. Water extracts without crude polysaccharides from mycelia of B. edulis had the highest ACE inhibitory activity (IC50 = 0.084 ± 0.011 mg/mL). Crude exopolysaccharides of B. edulis had higher antioxidant activity. Bioconversion with the fungus was proven to be a novel, practicable way to recycle shrimp by-products.  相似文献   

9.
Aquatic ornamental species trade is a growing multimillion dollar industry. Over the past several years, many freshwater shrimp have been growing in popularity in the aquarium industry. This study evaluated the larval culture of the popular aquarium red front shrimp, Caridina gracilirostris (Atyidae). We found that the optimal larval and postlarval rearing conditions were 15 ppt, 27 C, fed with a phytoplankton mixture (Phycopure), and at the stocking density of 25 per L. Under these conditions, the newly hatched larvae developed, through six zoeal stages, into postlarvae in 15 d, with a survivorship of 90 ± 8%. The postlarvae acclimated to freshwater when they reached 69 d posthatch.  相似文献   

10.
Abstract— This study was conducted in the semiarid region of Bahia Kino, Sonora, Northwestern Mexico to determine the feasibility of farming yellowleg shrimp Penaeus californiensis during the winter season in ponds with less than 5% daily water exchange and aeration. Four aeration rates (0, 6, 12, and 24 h/d) were used in the study. Mean growth rates ranged from 0.41 to 0.53 g/wk with the highest growth rate in ponds with 12 h of aeration ( P × 0.05). Survival ranged from 50 to 52% and did not differ among treatments. Shrimp yield ranged from 1,012 to 1,208 kg/ha, with the highest yields from ponds with 6 and 12 h of aeration ( P × 0.05). Feed conversion ratios ranged from 2.3 to 2.8, with lower values in ponds with 12 and 6 h of aeration ( P × 0.05). Results suggest that winter culture of yellowleg shrimp is possible and that 6 h of aeration is sufficient to maintain good water quality conditions.  相似文献   

11.
Two growth trials were conducted to evaluate and confirm the efficacy of a porcine meal (PM) with high protein content (>90%) as an alternative feed ingredient in commercial‐type feed formulation for Pacific white shrimp, Litopenaeus vannamei. Six experimental diets were formulated for the two growth trials. The first five diets contained increasing levels (0, 1, 2, 4, and 6%) of PM as a replacement for soybean meal in a plant‐based diet with low inclusion level (6%) of fish meal (FM). The last experimental diet was produced utilizing 4.2% PM to completely replace FM. In Trial 1, shrimp (1.5 g initial mean weight, 20 shrimp/tank, n = 4) were offered test diets for 6 wk in a semirecirculation system. At the end of Trial 1, shrimp fed with the diet containing 6% PM exhibited significantly enhanced weight gain (WG), feed conversion ratio (FCR), and survival compared to those fed with the diet devoid of FM. As survival was poor across all treatments and different densities could mask growth results the trial was repeated. In Trial 2, shrimp (0.85 g, 15 shrimp/tank, n = 4) were offered diets for 6 wk. Dietary supplementation of PM at 6% significantly improved WG, FCR, and apparent net protein retention in contrast with the treatment devoid of FM, confirming the same trends in Trial 1. No significant difference was detected in protein, lipid, moisture, and mineral profiles of whole‐body shrimp as well as survival across all the treatments. Results of this study indicate that PM is a good high protein source in shrimp feeds, which can be included up to 6% in the low FM‐based diet without compromising the growth of shrimp.  相似文献   

12.
ABSTRACT

This study developed and evaluated dry artificial fish bait for trap fishing utilizing tuna red meat (TRM) and shrimp head powder (SHP), aiming to replace the usage of edible fishes, such as sardines and squids, as bait. A total of 23 dry baits were prepared and tested for stability in seawater and acceptance by tilapia. Based on the stability and acceptability test results, two baits were selected as ideal and were further tested for protein leaching and dry matter loss in seawater. The tests revealed that the stick-shaped bait containing 61% TRM and 15% SHP was the ideal bait, with a protein leaching rate of 24.82 mg/g/h and dry matter loss of 36.6 mg/g/h. The catch rate of the traps baited with the artificial fish bait was significantly higher (P < 0.05) than those baited with squid meat (17 Nos/trap) and sardines (23 Nos/trap). Further, the catch rate of traps baited with artificial bait (38 Nos/trap) was found to be comparable with those baited with raw shrimp head wastes (SHW) (40 Nos/trap). When the bait was concentrated with 0.1% sodium benzoate, shelf life was extended by up to 6 months.  相似文献   

13.
近几年,我国的南美白对虾养殖业发展迅速.对虾产量大幅度上升,而对虾出口却又因欧美等进口国的禁令或限制措施而受阻,再加上对虾上市时间过于集中在每年8、9、10月份.造成国内对虾市场供过于求,对虾价格低迷,严重挫伤了虾农的生产积极性。为了探索对虾均衡上市的方法,增加虾农的收入,笔者于2003年9月中旬在广东省中山市横栏镇进行了南美白对虾冬季大棚精养试验,试验取得了良好的经济效益和社会效益。  相似文献   

14.
A study was conducted to evaluate alternative protein supplements that could be used to reduce the cost of formulated crayfish diets. Red swamp crayfish Procambarus clarkii were held in the laboratory for 9 wk and fed 30% crude protein diets containing isonitrogenous mixtures of plant and animal protein in a 65:35 ratio. Combinations tested were: soybean meal/menhaden fish meal (SOY/FSH); cottonseed meal/menhaden fish meal (COT/FSH); soybean meal/meat and bone meal (SOY/MB); cottonseed mealheat and bone meal (COT/MB); soybean meal/meat and bone meal/ blood meal (SOYIMB-B); and cottonseed meal/meat and bone meal/blood meal (COTIMB-B). Comparison of crayfish weight gain, feed efficiency ratio, apparent net protein and energy retention, and body composition indicated that SOY/FSH was the best protein combination tested. Weight gain was reduced when cottonseed meal replaced soybean meal in diets that contained either fish meal or meat and bone meal. Feed consumption of crayfish fed SOY/MB-B and COT/MB-B was lower than that of crayfish fed other diets containing the same plant-protein supplement and weight gain was lower in crayfish fed blood meal in all but one case. Differences in amino acid composition and amino acid availability of protein supplements, inhibitory effects of gossypol in cottonseed meal, and reduced consumption of diets containing blood meal could have contributed to diet effects. Results suggest that soybean meal is a better dietary protein source for crayfish than cottonseed meal, menhaden fish meal is better than meat and bone meal, and both fish meal and meat and bone meal are superior to a 60:40 meat and bone meal/blood meal mixture. However, cottonseed meal, meat and bone meal, and meat and bone meal/blood meal mixtures could be useful as lower-cost alternatives to soybean meal and fish meal in diets for pond-raised crayfish, since the apparent lower protein (amino acid) quality of these ingredients would be unlikely to depress growth of crayfish that have access to natural food in ponds.  相似文献   

15.
16.
The ability of Novacq to improve resilience of black tiger shrimp, Penaeus monodon, to infection and mortality induced by gill‐associated virus (GAV) was investigated. Over a 26‐d period, shrimp were fed pellets with or without 10% Novacq. Following this, four replicate tanks, each containing 10 shrimp that had been fed either diet, were maintained as‐is, injected with saline or injected with GAV inoculum (i.e., 40 shrimp for each of the six groups). For shrimp (n = 20) in two of each group of four tanks, survival was monitored daily over 14 d and a pleopod was sampled from each shrimp on Days 0 and 14. For the other two tanks, a pleopod was sampled from each shrimp on Days 0, 3, 7, 10, and 14 to track changes in GAV loads over time. Survival was significantly higher (P < 0.05) from Day 7 onward among the group fed Novacq. GAV infection loads appeared to vary more between individuals in the Novacq diet cohort, but overall were not reduced significantly at any time points post‐challenge compared to shrimp tested from the Control diet cohort.  相似文献   

17.
Superintensive shrimp culture in zero‐exchange, biofloc‐dominated production systems is more biosecure and sustainable than traditional shrimp farming practices. However, successful application of this technology depends upon optimizing dietary formulations, controlling Vibrio outbreaks, and managing accumulative changes in water quality and composition. A 49‐d study investigated the effect of two commercial feeds of differing protein content and an indoor limited‐exchange, biofloc‐dominated culture environment on Litopenaeus vannamei performance and tissue composition, water quality and ionic composition, and Vibrio dynamics. Juveniles (5.3 g) were stocked at 457/m3 into four 40 m3 shallow raceways containing biofloc‐dominated water and fed one of two commercial feeds with differing protein content, 35 or 40%. Shrimp performance, Vibrio populations, and changes in shrimp and culture water composition were monitored. There were no significant differences (P > 0.05) in shrimp performance (survival, weight, growth, specific growth rate, total biomass, yield, feed conversion ratio, and protein efficiency ratio) or proximate composition between feed types. The 40% protein feed resulted in higher culture water nitrate and phosphate concentrations, alkalinity consumption and bicarbonate use, and higher phytoplankton density. The presence of Vibrio, specifically Vibrio parahaemolyticus, reduced shrimp survival. This survival decrease corresponded with increased culture water Vibrio concentrations. Culture water K+ and Mg2+ increased significantly (P < 0.05), and Sr2+, Br?, and Cl? decreased significantly (P < 0.05) over time. While Cu2+ and Zn2+ did increase in shrimp tissue, no heavy metals accumulated to problematic levels in culture water or shrimp tissue. These results demonstrate the importance of monitoring Vibrio populations and ionic composition in limited‐exchange shrimp culture systems.  相似文献   

18.
The present study aims to understand the influence of freeze-dried shrimp (Penaeus monodon) meat (SM) at different levels (2.5, 5, and 10%; w/w) in pasta processing. The rheological characteristics studies of SM-wheat flour blends indicated that dough stability increased with the increased addition of SM in the blends, whereas farinograph water absorption and amylograph peak viscosity decreased. Cooking loss increased with increasing levels of SM in the pasta (7.3% in 10% SM pasta; 6.7% in control pasta). However, all pasta samples were in the acceptable range. Color analysis of the pasta sample indicated that the L values increased with increasing levels of pasta. The instrumental texture of cooked pasta indicated that 10% SM pasta was significantly (p < 0.05) firmer (1.84 N) than that of the control (1.35 N). Microstructure studies revealed that incorporation of SM in the pasta had a better protein network. Pasta with 5% SM had the highest mean score for all sensory attributes, with increased levels of essential nutrients, fatty acids such as eicosapentaenoic acid and docosahexaenoic acid, and amino acids such as lysine.  相似文献   

19.
White spot disease caused by white spot syndrome virus (WSSV) poses major problems that result in huge economic losses each year in shrimp aquaculture throughout the world. In the present study, microsatellite‐based DNA fingerprints have been compared between naturally occurring WSSV disease‐resistant and susceptible populations of giant black tiger shrimp, Penaeus monodon, to find DNA markers. For the first time, we report here a microsatellite locus, which, after amplification by polymerase chain reaction, provides a highly statistically significant DNA fingerprint of 71 bp, only in disease susceptible populations but not in disease‐resistant shrimp populations, whereas a 317 bp band is common in both. The absence of the former DNA marker will be very useful to identify disease‐resistant broodstock of P. monodon for marker‐assisted selection in breeding programs to generate disease‐free shrimps (P. monodon) in the aquaculture industry.  相似文献   

20.
Potential feeds, feeding schedules, and feed supplements for growing M. rosenbergii postlarvae to a juvenile size of 0.5 g were evaluated. Postlarvae were grown in 69 L aquaria for 6 to 9 weeks at densities of 1.3 or 2.0/L at a water temperature of 28 C. An experimental diet (HFX-EXD-86X) and four commercially available feeds (Purina Trout Chow No. 2, Silver Cup Fish Feed—Salmon No. 3, Zeigler Shrimp Post Larval Granules No. 3, and MFC Clover Brand 38% Catfish Fingerling Crumbles) were tested. Prawns fed Purina Trout Chow No. 2 had the best survival and yield. Four feeding schedules were then evaluated with Purina Trout Chow No. 2 as the only food: once daily (at 1600 h), twice daily (at 0800 and 1600 h), twice daily (at 0800 and 2000 h), and three times daily (at 0800, 1600, and 2400 h). Prawns in the oncedaily treatment exhibited the best survival, final weight, yield, and food conversion ratio. A oncedaily frequency was then used to test the effects of supplementing the Purina diet with beef liver, squid mantle, codfish muscle, or cooked (scrambled) chicken egg, at 20% dry weight of the total diet. Prawns fed the beef liver supplement had the best final weight and yield.  相似文献   

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